/**
*      author: Y_Yao
*      created: 2025-02-07 21:20:00
**/

#include<bits/stdc++.h>

#define int LL
using namespace std;
using LL = long long;
const LL LLINF = 1e18;
const int INF = 0x3f3f3f3f;
const int N = 1e6 + 6;
int a[N];
int n,m;

bool check(int mid)
{
    int count = 0;
    for(int i = 1;i <= n;i++)
    {
        if(a[i] > mid)
        {
            count += a[i] - mid;
        }
    }
    return count >= m; 
}

void solve()
{
    cin >> n >> m;
    int l = 0,r = -INF;
    for(int i = 1;i <= n;i++)
    {
        cin >> a[i];
        r = max(r,a[i]);
    }
    //cout << r << endl;
    while(l < r)
    {
        int mid = l + ((r - l + 1) >> 1);
        if(check(mid)) l = mid;
        else r = mid - 1;

        //cout << mid << endl;
    }
    cout << r << endl;
}

signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);

    int t = 1;
    //cin >> t;
    while(t--)
    {
        solve();
    }
    return 0;
}